Roof construction



Feb. 22 1927. 1,618,768

v H. E. MARKS ROOF CONSTRUCTION Filed March 25. 192,5

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HERBERT l. MARKS, F SEWICKLEY, PENNSYLVANIA..

ROOFv CONSTRUCTION.

application mea nasen 25,1925. serial 110.15141.

The invention relates to roof decksand to the construction of slabs forforming them, and the object is to 'provide a fireroof roof deck whichis elfective for its Intended purpose, and which is very economical toconstruct, because. among other reasons, of the` simplicity of the slabsof which it is made, the lightness of their weight, and the ease withwhich they may be laid to forma deck. v

The invention isillustrated in the accompanyin drawings, of which Fig. 1isa plan view o a portion of a roof deck; Fig. 2 a detail sectional viewto enlarged scale taken on the line II--IL Fig. 1, showin a pair ofadjacent slabs as they appear willen laid upon supporting members andbefore the roofris finished;y Fig. 3 a view similar to Fig. 2, show inthe completion of a joint between the si es of adjacent slabs; Fig. 4 adetail sectional view to enlarged scale i taken on the line IV-IV, Fig.l; Fig. 5

a plan view of portions of adjacent sides of av pair of slabs showingmodifications of construction, and Fig'. 6 a sectional view taken on theline VI-VI, Fig. 5.

In the practice of this invention a roof deck is formed of aplurality ofslabs,each of which is made of a lurality of wooden boards of sullicientthic ess in proportion to their s an lengths to sustain a required roofloa The load-sustaining portions whichA enter into the construction of aslab are held in slab-formation, by a board of relproofing materialwhich is firmly attac ed to the faces of the wooden boards and issuiciently rigid totie the boards togther and maintain them in the -formof a..

b. The preferred form of board for this purpose is what is known as avplaster or gypsum board. While a single gypsum board may be used, it ispreferred to use two, one attached to the lower, and the other to theupper faces of the wooden boards.

Having reference to the illustrati-ve cmbodment of the invention, alroof deck is erally indicated in Fig. 1 as being di'lmed of a luralitof slabs A resting on purlins 41. e sla s may similarly rest uponsuburlins or upon rafters, the term purlins ing here used as includingboth sub-purlins and rafters;'and the slabs may, as far as concerns somefeatures of the invention, be otherwise suplported.

As shown in Fi 2 eac slab A is formed ,applied to adjacent slabs may besuch 4of a plurality of wooden boards 2 having rigid boards 3 offireproofing material attached to their lower faces. The wooden boardspreferablyY have plane-faced sides as shown in Fig. 2, but may bedove-tailed, as indicated at 4 in Fig. 6. As previously explained, rigidboards 5 of fireprooiing material are preferably firmly attached to thetop faces of boards 2'to assist the lower boards 3 in holding the woodenboards in slab formation, as well as to {ireproof the tops of the slabs.The attachment of the lower and upper boards 3 and 5 to the woodencore-forming boards 2 is preferably effected by nailing the former tothe` latter asshown in Fig. 2, but may be effected by cementing the-fireprooiing boards to the wooden boards as indicated at-GinFig. 6,silica cement preferablybeing used for this purpose. v

In addition to the provision of rigid boards of ireproofing material forperforming the double function of holding load-sustainin wooden boardsin slab formation and o ireprooling their faces, the invention in itspreferred form contemplates the provision of fireproofing material atthe edges of the Y wooden boards at the sides of the slabs. This ispreferably done by extending the ed es of lower boards 3 beyond thesides of sla s A, as indicated at 7 in Fig. 2, to form a support foroementitious frep'rooiing material which may be poured upon theprojecting ends 7 'and between the adjacent sides of the wooden boardsafter the slabs have been laid in position. Such a filling offireprooing materialpreferably of gypsum, is

indicated at 8 in 1g. 3.

It will be understood that unequal loads as cause suflicient deiiectionof one slab with relation to the other to breakthe {ireprooinv seal 8between the 'sides of the slabs, an j also to break or injure thewaterproofing layer which is customarily applied to the M top of thedeck. To resist such relative` as shown in Fig. 1. They may be, andpreferably are, nailed to boards 2. as shown in Fig. 3, but may becemented to them as shown in Fig. 6.

Instead of providing a monolithic fill 8 of fireproong material betweenthe sides of adjacent slabs as shown in Fig. 3, the sides of the slabsmay be iireproofed by applying to them bodies 10 of gypsum or otherfireroofing material as indicated in Fig. 6.

hen this is done, both top and bottom boards 3L and 5 preferably extendbeyond the wooden'boards 2 at the sides of the slabs to form pockets forreceiving and holding the fireproofing bodies 10. When the slabs are soconstructed, top boards 3Il are preferably notched ut at their edges atsuitable intervals as indicated at 1l in Fig. 5, and plates 12 placed inthe notches and attached to the upper faces of boards 2 to resistrelative vertical movement between the adjacent sides of the slabs.

As shown particularly in Fig. 4. the ends of the slabs preferably restupon the upper ianges of purlins l. To hold them in position theirbottom faces may be provided with suitable attac-hing members, such asscrew clips 15, constructed to engage the flanges of the purlins. Fortying the slabs together at their ends, top plates 5 are preferably setback from the ends. and a j oint-spanninor plate 16 laid between theirends and nailed or otherwise attached to the upper faces of boards 2.

Assuming, by way of example and not of limitation, that roof purlins arespaced at six foot intervals, a slab may be formed of wooden boardsabout eightinches wide, one and a half inches thick and about six feetlong. The space between adjacent sides of the slabs for receivingfireproofing material may be about one inch wide. The slabs may be madeata factory and shipped to the site of erection, or may be made at thesite. In either case they may be formed at a. minimum cost. They arelight in weight, and accordingly may be easily raised to a roof andeasily manipulated to lay them upon supporting members. If the sides ofthe slabs are provided with a ireproofing material after the slabs havebeen laid in position, this may be quickly and economicallyA done byworkmen standing upon the slabs.` Thereafter, the sides of the slabs aretied together by lates 9 or 12, and their ends by plates 16. fter thedeck is completed it may be covered by any desired form ofweaitther-proofing` or other protecting materia Not only is theremanifest economy in the construction of the slabs and in laying a roofwith them, but an indirect economy arises from their lightness inweight` because the supporting structure may be correspondingly lig t.

According to the provisions of the patent statutes, I have explained theprinciple and operation of my invention, and have illustrated anddescribed what I now consider to represent its best embodiments.However, I desire to have it understood that, within the scope of theappended claims, the invention may be practicedby other forms ofconstruction than that particularly shown and described.

I claim aslmy invention:

l. In a roof, the combination with spaced purlins, of a roof deckcomprising a plurality of preformed slabs resting at their ends uponsaid purlins, each slab being formed of a plurality of load-sustainingWooden boards having firmly attached to their lower faces rigid boardsof fircproofing material holding the boards in slab formation, saidboards of ireprooiing material projecting beyond the sides of the slabs,and cementitious ireprooting material at the sides of the slabssupported by said projecting portions of said ireproong boards.

2. In a roof, the combination with spaced purlins, of a roof dec-kcomprising a plurality of preformed slabs resting at their ends uponsaid purlins, each slab comprising a plurality of load-sustaining Woodenboards having firmly attached to their lower faces a rigid board offireprooing'material holding the wooden boards in slab formation, saidboards of reproofing material projecting beyond the sides of the slabs,ccmentitious ireproofing material laid at the sides of the slabs uponsaid projecting portions of the ireprooiing boards, and a rigid platespanning the adjacent sides of slabs and attached to their faces forresisting relative vertical movements of said slabs at their adjacentsides.

3. In a roof, the combination with spaced purlins, of a .roof deckcomprising a plurality of preformed slabs restin at their ends upon saidpurlins, each s ab being formed of a plurality of load-sustaining woodenboards having rigid boards of fireproofing material irml attached totheir upper and lower faces olding the wooden boards in slab formationfor handling, said ireproofing boards on the lower faces of the slabsprojecting be ond the sides of the slabs monolithic fil s ofcementitious fireproodng material betweenthe sides of said slabs suported by said rojecting portions of said re roofing boar s, and rlgidplates spanning t e adjacent side of slabs and attached to their facesfor resisting relative vertical movements of the slabs at their adjacentsides.

4. In a roof, the combination with spaced purlins, ofa roof deckcomprising a lurality of preformed slabs resting at t eir ends upon saidpurlins, each slab comprising a core forme of a plurality ofload-sustaining wooden boards havin rigid boards yof reprooling materialfirm y attached to `boards on the upper faces of the sla s being setback from both sides of each slab, and rigid plates spanning theadjacent sides of slabs and attached to their upper faces for resistingrelative vertical movements of the slabs at their adjacent sides.

5. In a roof, the combination with spaced purlins, of a roof deckcomprising a plu- -rality of preformed slabs resting at their ends uponsaid purlins, each slab comprising a core formed of a plurality'ofload-sustaining wooden boards having rigid gypsum slab, said boardsfirmly attached to their upper and Y, lower faces holding the woodenboards in slab formation prior to the laying of the psum boards on thelower faces of the sla s projecting beyond both sides of each slab,monolith1c fills of ireprooing cementitious material between the sidesof adjacent slabsand supported by said projecting portions offireprooting boards, said gypssum boards on the upper faces of the slabeing set back from both sides of each slab, and rigid gypsum boardsspanning the adjacent sides of slabs and attached to their upper facesfor resisting relative vertical movements of the slabs at their adjacentsides.

6. A roof deck comprising spaced purlins, and a plurality of preformedslabs restin at their ends upon said purlins, each sla comprisin a coreformed of a plurality of load-sustaining wooden boards having rigidboards of reprooling material attached to their upper and lower facesholding the wooden boards in slab formation prior to the laying of theslab, said fireprooing boards on the lower faces of the slabs projectingbeyond both sides of each slab` monolithic fills of ireproofingcementitious material between the sides of adjacent slabs and supportedby said projecting portions of ireproong boards, said lreproofing.

boards on the upper faces of the slabs bein setback from both sides ofeach slab rigi plates spanning the adjacent sides of slabs and attachedto their upper faces for resisting relative vertical movements of theslabs at their adjacent sides, said fireproofing boards o'n the upperfaces of the slabs beingv set back from the ends of the wooden boards,and rigid plates spanning the adjacent ends of slabs and attached totheir upper faces between the ends of said u per fireprooin boards andtying the ends o the slabs toget er.

In testimony whereof, 'I sign my name.

HERBERT E. MARKS.

